The conventional way of visbreaking polypropylene (PP) is by use of organic peroxides. While organic peroxides increase the melt flow rate (MFR) of the resin, the byproducts which are generated (typically alcohols, ketones, aldehydes, etc.) impart strong taste and odor to the resultant product. The carbon-carbon (C—C) initiators do not have any oxygen in their structures and as such do not generate those objectionable taste and odor components.
WO 2012/096962 discloses the use of “C-C containing” compounds as antioxidants. WO 2012/074812 discloses the use of a “C-C containing” compound as an impurity scavenger in the polymerization of block copolymers. WO 2010/0108357 discloses the use of a “C—C containing” compound as a crosslinking agent in a polymer composition. U.S. Pat. No. 5,268,440 discloses the use of a C—C initiator in an LDPE process. U.S. Pat. No. 6,967,229 discloses the use of “C—C containing” compounds in the formation of golf ball components. US 2006/0047049 discloses “C—C containing” compounds in flame retardant compositions. There remains a need for new processes to form visbroken propylene-based polymers with improved properties. This need has been met by the following invention.